能实现多功能。既可做倒计时秒表,又可进行定时，还可以通过扩展完成其他功能，而且功能的相互转换也十分简单...

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能实现多功能。既可做倒计时秒表,又可进行定时，还可以通过扩展完成其他功能，而且功能的相互转换也十分简单-To achieve multi-functional. Can do the countdown stopwatch, but also to timing, but also by extending the completion of other functions, and inter-conversion functions is also very simple and